Cryptocurrencies are acting as anything but, though. In 2015 electronic cash wasn't really a thing in my country (it's still got a long way to go today). I tried using Bitcoin. It was slow, difficult to use, and the value was prone to wild swings. I wanted Bitcoin or something similar to succeed as a currency. But it's all been taken over by speculators and scammers.

When I moved to Australia I found that I could just use AUD electronically. Fast, easy, stable, and fee-free.

USD works the same within the US, I have found for decades.

And I don't mean that in any negative way; I mean what you said seems true in Australia and in the US.

Lol.. the primary function of all cryptocurrencies have been to act as yet another line on a graph for people to make bets on. The moment a decentralised currency is actually used for normal trade and business by more than a few people it will be shut down.